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I have a vendor telling me that QQ-

I have a vendor telling me that QQ-

(OP)
I have a vendor telling me that QQ-P-35C, TYP 2 VII has been superseded by AMS-2700. I can't find anything on this so I'm hoping someone here has much greater research powers and can point me in the right direction. Thank you all.

RE: I have a vendor telling me that QQ-

In the military and aerospace context, "superseded" generally means that the rights to the standard have been sold to the highest bidder. It does not mean that the standard has changed in a practical way, though this is possible, if the new holder (in this case the SAE) has changed or revised the spec since they took control of it. In this case I think they have, but usually, it's a cut-and-paste with the new letterhead.
I looked up the spec here: http://quicksearch.dla.mil/ and found the original process.
I can also find the current spec here: www.astm.org
And the alternate here: www.sae.org

I happen to have called up these spec's recently, and it turns out that the SAE did not completely adopt the QQ-P-35 processes. There are several types and classes of passivation included in these specs. I have a vendor that can still accomplish the QQ-P and another that prefers the AMS spec. I still get the passivation that I want.

If you are selling your product to the armed forces of the United States of America, then you are forbidden from specifying or applying the old QQ-P-35 to your products now that they are superseded. However, if you are a civilian, or selling internationally, or procuring/producing for a government that is not the US of A, then you can use any process that your customer deems satisfactory.

Remember, any production process is just "one" way to do something. It is not the "only" way to do something.

STF

RE: I have a vendor telling me that QQ-

From Notice 3 of QQ-P-35:

QQ-P-35C, dated 28 OCTOBER 1988, NOTICE 1 dated 4 APRIL 1997 and NOTICE 2 dated 14 NOVEMBER 1997, are hereby canceled. Future acquisitions for this product should refer to American Society for Testing and Materials (ASTM) specification ASTM A967, “Standard Specification for Chemical Passivation Treatments for Stainless Steel Parts”, or, SAE Aerospace Materials
Specification (AMS) AMS-QQ-P-35, “Passivation treatments for Corrosion-Resistant Steel”. Aerospace applications require the use of AMS-QQ-P-35.

The above guidance is for DoD activities only and does not apply for non-DoD uses. Users are cautioned to evaluate these documents for their particular applications before citing them as a replacement document.

AMS-QQ-P-35 was cancelled and superseded by AMS 2700 from the AMS-QQ-P-35 cancellation notice:

This specification has been declared “CANCELLED” by the Aerospace Materials Division, SAE, as
of February, 2005, and has been superseded by AMS 2700. The requirements of the latest issue of
AMS 2700 shall be fulfilled whenever reference is made to the cancelled AMS-QQ-P-35, utilizing the
“Type” designation noted in the following table. By this action, AMS-QQ-P-35 will remain listed in the Numerical Section of the Index of Aerospace Material Specifications, noting that it has been superseded by AMS 2700.

AMS 2700 added the use of a citric acid.

RE: I have a vendor telling me that QQ-

(OP)
Thanks for all the great information. Is there any requirement for the notes section of the drawing that call out QQ-P-35-C must be changed to AMS-2700?

RE: I have a vendor telling me that QQ-

"Is there any requirement for the notes section of the drawing that call out QQ-P-35-C must be changed to AMS-2700?"

see Sparweb's post above.

normally/often/sometimes/"only when we're lazy" Eng'g drwgs accept using superceded specs. Then when Planning call tell them the current equivalent spec.

another day in paradise, or is paradise one day closer ?

RE: I have a vendor telling me that QQ-

Many companies have formalized materials, fab processes and parts substitutions for each aircraft type... or groups of acft... by 'substitution documents', that have been vetted and pre-approved engineering as 'equivalent or better-than'.

In essence, these documents [or drawings], provide 'old' base numbers [materials, processes, parts] in column 'A'; and then indicate in adjacent column 'B' one or more acceptable options. For the OEM and certain customers... such as DoD... these are formal acceptance for the substitute and requires no further engineering approval or documentation. As time goes-on the listing base number and substitutes can grow 'huge'.

CAUTION. These substitution documents/drawings almost-always allow use of the original material, process or part... so 'forward and backwards' substitutions are acceptable. IF a drawing or document is modified so-as-to revise what is acceptable... IE AN4 bolt is replaced by NAS6304 bolt on the PL and FD, then going backwards [IE: to the AN-4 bolt] is generally prohibited... unless specifically allowed by exception on the drawing/document.

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: I have a vendor telling me that QQ-

Also beware that some newer version transition from directives of how to do something to acceptance docs that tell what the expected result is. Which means that you will have to investigate exactly what a supplier intends to do to meet the spec and may have to create an in-house standard to control that method.

A long standing example of this sort is the MIL Grease specs, which typically fail to detail all the chemistry involved, meaning that greases that meet the performance requirements in the spec may not be interchangeable.

RE: I have a vendor telling me that QQ-

Aerospace vendors are typically operating under AS9100 and/or NADCAP certification requirements. This means they are qualified for each of their processes, and they follow the specification procedures to the letter. Due to the costs involved with maintaining certification to perform a specific process, vendors often don't continue performing work according to cancelled specifications, due to limit demand. If your engineering drawing or purchase order specifies a cancelled process like QQ-P-35 with no substitution, and your AS9100/NADCAP vendor is no longer qualified to QQ-P-35, they will decline to accept the work. Their AS9100/NADCAP quality procedures require documenting that they performed the process in accordance with the specification requirements, and they will usually provide you with a Certificate of Conformance (CofC) which basically states they did exactly what you asked them to do. With this particular situation, the best thing to do would be to issue an engineering change notice that permits use of a current passivation process like AMS 2700 or ASTM A967 in place of QQ-P-35. Very quick and easy to do.

Here's a link to the first 2 pages of AMS-QQ-P-35A if you want to read about it.

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